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arXiv · 1310.0820

Effects of the imaginary inflaton component in supergravity new inflation

David Nolde
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Abstract

When models of new inflation are implemented in supergravity, the inflaton is a complex and not a real scalar field. As a complex scalar field has two independent components, supergravity models of new inflation are naturally two-field models. In this paper, we use the delta N formalism to analyse how the two-field behaviour modifies the usual single-field predictions. We find that the model reduces to the single-field limit if the inflaton mass term is sufficiently small. Otherwise, the imaginary inflaton component reduces the amplitude A_s and the spectral index n_s of the scalar curvature perturbations. However, the perturbations remain nearly Gaussian, and the reduced bispectrum f_NL is too small to be observed.

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David Nolde. 2013-11-12. Effects of the imaginary inflaton component in supergravity new inflation. https://doi.org/10.1088/1475-7516%2F2013%2F11%2F028

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